5 Scenarios for Harnessing the Atom: 2008 Edition

Now this is a very interesting article on a possible nuclear powered future and how it will look. Remember the name of the game when it comes to nuclear power is that you do not want waste you have to dump under Yucca Mountain and you do not want to proliferate more bombs. Here are the 5 scenerios where these goals are possible. I hope new Energy Secretary Ken Salazar is taking notes. (I'm partial to the Liquid Fluoride Thorium Reactors and the Fast Breeder Reactors in a closed fuel cycle myself.)

Five nominal scenarios based predominantly on specific reactor types:

• Advanced light water reactors (LWRs) and/or gas-cooled thermal reactors on a once through fuel cycle

In this scenario, LWRs and gas-cooled reactors such as the pebble bed reactors operate on a once-through fuel cycle through 2050 (as described in the MIT study) and also to the end of the century. The reactors will be fueled by low-enriched uranium. Spent fuel will be put directly into geological repositories.

• Actinide burning based on fast reactors

This is the vision of the Global Nuclear Energy Partnership (GNEP). Spent fuel fromLWRs and from a fleet of fast reactors will be reprocessed to separate plutonium andother transuranics (TRU – americium, curium, and neptunium). These will befabricated into fuel for fast reactors and will be fissioned in the fast reactors in several cycles, such that the plutonium and other TRU are eventually mostly burned away. The fission products will be put into geological repositories.

• Fast breeder reactors in a closed fuel cycle

We imagine, in equilibrium, a division of LWRs and fast breeders in roughly a 55-45 ratio, similar to that described in the MIT study. Spent fuel from both types of reactors will be reprocessed and the separated plutonium used to start-up and re-fuel the breeder reactors.

• Thorium fuel cycles

Several different thorium cycles are considered. In particular, we note the possibility of breakeven breeding in a molten salt reactor. While such a reactor requires enriched uranium (typically 20 % U-235) for startup, relatively little further supplies of enriched fuel are required during subsequent operation. The U-233 produced by neutron absorption in Th-232 is never separated from the fuel, and it is also denatured by the addition of U-238 which means that isotope separation would be required to obtain weapons-grade U-233. In addition, the isotope U-232, which has a high gamma-emitting daughter, is produced during reactor operation, thus furthercomplicating attempts to obtain weapons-usable U-233 from this cycle.

• Nuclear batteries in a hub-spoke configuration

At a central facility, reactors nominally in the range of 20-100 MWe would be fueled either with 20% uranium or plutonium, sealed, and then transported to countries deploying the reactors. The reactors would not need to be refueled during their core life, nominally 20 to 30 years, at the end of which time they would be sent back to the central facility, where the plutonium would be separated and re-fabricated into cores for the replacement reactors.